The demand for wood products is ever increasing. However, both the quantity and quality of new wood resources is decreasing thereby resulting in increased building expenses and decreased building quality. A considerable inventory of otherwise sound lumber, much of it from old growth forests, is disposed of annually because it has been used and thus has fasteners embedded therein. Much, if not most, of this lumber could be profitably reused if only the fasteners embedded in it could be easily and inexpensively removed without undue damage to the lumber product (often occasioned by nail-removing equipment just to get access to the fastener head). Excessive damage to used lumber often makes the product unusable, but at the very least causes the used product to be dropped in grade to a use below its potential had it remained relatively undamaged.
When undertaking nail extraction, it is often the case that its head is broken away (or that it was headless to begin with) and/or is recessed into the wood material. In the case of screws, it is also common for a broken shank to remain embedded in the host material and for grooves in the head for driving the screw to be stripped away. In all such cases, removal of the fastener has been heretofore extremely difficult without excessive damage to the host material (i.e., the wood fiber for example) within a large radius of the fastener's shank.
Many devices have been heretofore suggested and utilized for aiding in the removal of nails and/or screws from wood. Such devices have included simple lever tools such as claws and pries, mechanized pullers having opposed jaws with limited wood cutting capability, as well as impact tools for driving the fastener through the host. Many such tools necessarily result in excessive damage to the host material, and few of the heretofore known devices are effective where the shank of the fastener is headless and/or where the fastener is totally recessed in the host material.
Of the heretofore known devices for removal of fasteners from yieldable materials such as wood, plastic or the like, many are cumbersome and do not lend themselves to rapid and repeated utilization (i.e., are labor intensive). Most are targeted to specific kinds and sizes of fasteners, as well as specific fastener positions and orientations relative to the host material surface. Moreover, many such devices are quite limited in application, often necessitating more than one tool to remove a single fastener.